Valves



April 7, 1970 L. P. SCHMITZ 3,504,706

I VALVES Filed July 16, 1968 2 Sheets-Sheet 1 mvemon LOTHAR PETER scHmTz y 640m, 5 rfiwwd q April 7, 1970 L. P. SCHMITZ 1 3,504,706

VALVES Filed July 16, 1968 2 Sheets-Sheet 2 F/G.2. 2o 17 411141 70 I a l aka/IRE INVENTOR LOTHAR PETERSCHMII'Z.

United States Patent 3,504,706 VALVES Lothar Peter Schmitz, Pudsey, near Leeds, England, as-

signor to The Drum Engineering Co. Limited, Dudley Hill, Bradford, Yorkshire, England Filed July 16, 1968, Ser. No. 745,272 Claims priority, application Great Britain, Dec. 22, 1967, 58,389/ 67 Int. Cl. F16k 39/06 US. Cl. 137625.43 2 Claims ABSTRACT OF THE DISCLOSURE A rotary valve having a first position whereby a first and, a second port are connected to a third and a fourth port respectively, and a second position whereby the first and second ports are connected to the fourth and third port'respectively. The valve is radially balanced by fluid pressure.

The present invention relates to rotary valves.

According to the present invention a valve comprises a valve chamber having an internal surface of circular cross section and having first and second ports facing one another and located respectively at opposite sides of its axis and third and fourth ports which are spaced from one another in the direction of said axis and each located angularly between said first and second ports and a valve member in said chamber comprising axially spaced plugs which fit within the valve chamber at opposite ends of the locality of said ports and are connected to opposite ends of a barrier which fits within and extends across the valve chamber so that opposite ends of the barrier are spaced axially of the chamber and so that the axial extent of said first and second ports lies within the axial extent of the barrier such that in a first angular position the barrier connects the first port to the third port and the second port to the fourth port and in a second angular position it connects the first port to the fourth port and the second port to the third port, the said barrier being connected at its axially opposite ends to said plugs by connecting bars of smaller circumferential extent and smaller superficial area and connected to said plugs intermediate of its ends by connecting webs of greater circumferential extent and greater superficial area each of which webs bifurcates towards the barrier to provide a port between the bifurcation and the barrier, each of said webs and its bifurcation being formed with an external recess communicating with that side of the barrier remote th refrom.

If desired the barrier may permit communication between said first and said second ports when in an intermediate angular position between said first and said second angular positions.

The existence of a higher fluid pressure on one face of the barrier and a lower fluid pressure on the other face of the barrier gives rise to radial thrust; thus a high pressure difference across the barrier might render it difficult to turn the valve member. The net radial thrust on the valve member is minimised according to the invention by the provision of said connecting webs and said external recesses therein.

The invention is further described by way of example with reference to the accompanying d'awings in which:

FIG. 1 is a perspective view of the valve with part of the casing cut away to reveal part of the valve member;

FIG. 2 is a part sectional plan view looking down upon FIG. 1, and

FIG. 3 is a part sectional side view of the valve of FIG. 1 when inverted.

The valve casing or chamber 1 has a cylindrical bore 3,504,706 Patented Apr. 7, 1970 2, first and second ports 3 and 4 which face one another and are located at opposite sides of the axis of the bore and third and fourth ports 5, 6 which are spaced from one another in the axial direction and are located angularly between the first and second ports 3, 4.

The valve member comprises axially spaced cylindrically surfaced plugs 9, 10 at opposite ends of the locality of the ports 3, 4, 5, 6, which plugs are connected to opposite ends of a barrier 11 which fits within and extends across the valve chamber so that its opposite ends are spaced axially of the valve chamber and so that the axial extent of the first and second ports 3 and 4 lies within the axial extent of the barrier 11.

The barrier 11 is connected at its axially opposite ends to theplugs 9, 10 by connecting bars 13, 14 and, intermediate of its ends, is connected to the plugs 9, 10 by webs 15, 16 each of which bifurcates as indicated at 17 towards the barrier 11 to provide a port 19 between itself and the barrier 11.

Each of the webs 15, 16 and its bifurcation 17 has an external groove 20, 21 communicating with that side of the barrier remote therefrom.

Each of the plugs 9, 10 is formed with a groove in which is received a sealing ring 24. The righthand end of plug 10 is formed with a spindle 25 on which is mounted an operating handle 26.

The valve member is located axially of the casing 1 by means of a bolt 30 which is threaded into the casing and at its inner end engages in a groove 31 in plug 9.

In the position of the valve member relatively to its casing as shown in FIG. 1, port 3 is connected to port 6 and port 4 is connected to port 5. By turnin the valve member through 180 port 3 can be connected to port 5 and port 4 connected to port 6. If the valve is turned through from the position illustrated in the drawings all of the ports are interconnected.

If it is assumed that fluid at higher pressure enters at port 3 and is discharged through port 6 and fluid at lower pressure enters at port 4 and is discharged at port 5 then the higher pressure exerted on the front face of barrier 11 as viewed in FIG. 1 will tend to press the valve member towards the rearward internal surface of the valve chamber. This tendency however will be to some extent countered by exertion of the higher pressure forwardly against the larger area of the inner face of web 16 as compared with the smaller area of bars 14, by the existence of the lower pressure in groove 21 and also by the exertion of the higher pressure forwardly against the external surface of web 15 as a result of the transmission of the higher pressure along the groove 20. The forward pressures on the outer face of web 15 and on the inner face of web 16 are exerted at opposite sides of barrier 11 where radial pressure is exerted rearwardly thus rendering the valve member fairly well balanced radially.

I claim:

1. A rotary valve comprising a valve chamber having an internal surface of circular cross-section and having first and second ports facing one another and located respectively at opposite sides of its axis and third and fourth ports which are spaced from one another in the direction of said axis and each located angularly between said first and second ports and a valve member in said chamber comprising axially spaced plugs which fit within the valve chamber at opposite ends of the locality of said ports and are connected to opposite ends of a barrier which fits within and extends across the valve chamber so that opposite ends of the barrier are spaced axially of the chamber and so that the axial extent of said first and second ports lies within the axial extent of the barrier such that in a first angular position the barrier connects the first port to the third port and the second port to the fourth port and in a second angular position it connects the first port to the fourth port and the second port to the third port, the said barrier being connected at its axially opposite ends to said plugs by connecting bars of smaller circumferential extent and smaller superficial area and connected to said plugs intermediate of its ends by connecting webs of greater circumferential extent and greater superficial area each of which Webs bifurcates towards the barrier to provide a port between the bifurcation and the barrier, each of said webs and its bifurcation being formed with an external recess communicating with that side of the barrier remote therefrom.

2. A rotary valve according to claim 1 in which the second ports when in an intermediate angular position between said first and said second angular positions.

References Cited UNITED STATES PATENTS 3,146,795 9/1964 Retallick l37625.47 X

FOREIGN PATENTS 646,436 11/1950 Great Britain.

M. CARY NELSON, Primary Examiner M. O. STURM, Assistant Examiner US. Cl. X.R.

barrier permits communication between said first and said 15 251283 

